Rafter-scale.



No. 814,948. PATENTBD MAR. 13, 1906.

W. W. DWIGANS & J. M. ADAMS.

RAPTER SCALE.' APPLICATION FILED NOV. 15, 1905.

m "'"lv nini imma@ TOHNE YS To a/ZZ whom it may concern. i

yurrnn' 'sTATEs PATENT onirica I AND JOE M. ADAMS, OF ARKADELPHIA, ARKANSAS.

` vRAFTEFzsCALls.

' Speccation of Letters l'atent.` 1 Application filed November 15, 41905. Serial No. 287,452.

Patented March 13, 1906.

ABe it known that we, WILLIAM WESLEY DwIGANs and JOE M. ADAMS, citizens of the UnitedStates, and residents of Arkadelphia, in the county of. Clarkand State: of Arkansas, have invented a-newand-Improved Rafter- Scale, of which the following is a full, clear,

and exact description. A

This invention relates to mechanics tools. TheJ object of the invention is to provide a convenient plumb-scale for' finding thev lengths of rafters'fof various pitches and for different widthsof buildings.

The invention consists in the construction and combination of parts to be more fully described hereinafter and definitely set forth .in the claims.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the figures. l v

Figure 1 is a front elevation of the scale, showing a vportion of a level to which the me vention is conveniently attached. Fig. 2 is a vertical central section through the device. Fig. 3 is a front elevation of-the device upon a reduced scale, illustrating how the device is used in practice and showing the pointer thereof operating with one of its scales; and Fig. 4 is a view similar to Fig. 3, but representing the device in an opposite position and showin the pointer operating with an opposite sca e.

Referring more particularly to the parts, 1

represents the body of a spirit-level such las is used lby carpenters. At a convenient point on this body we attach a dial-case 2, the same being preferably mounted in a recess 3, formed in the face of the body 1, as will be readily understood. This dial-case is formed with a central hub 41, which is received in an opening 5, formed in the body, as'indicated, and this opening is counterbored at the rear, so as to form a recess 6. The jhub 4 ofthe case 2 isprovided on its inner face with a bore 7. This bore 7 receives a hub 8, 'which is formed on the inner face of a dial 9, and the lower edge 1() of this dialis graduated, as

shown. The rear side of the lower portion of the dial is provided with a counterweight .11, which normally holds the dial in the posit] on shown in Fig. 1. In this position the zerostraight rafters.

mark of the dial is disposed in a vertical line below'the center of the dial, and the degrees f are laid off successively fromrthis point in both directions. lVle prefer to mark the fortyfive-deg'ree lines on both sides by numerals, and on one side we-indicatethe thirty-degree mark, as shown. As viewed in Fig. 1, in the vertical central line of the dial', above the center thereof, we provide a plurality of threaded openings 12, which are adapted to receive a removable threaded pin 13. This pin affords means for attaching -a pointerlll, which is hung normally in a vertical position from a pivoting-pin 15, attached on the casing 2. It en ages the pin 13 by means of a longitudi.- na slot 16, through which the pin passes, as will be readily understood. On the upper portion of the face of the dial we provide a plurality of curves 17, which constitute scales. There are four of these 'scales disposed on each side of the central line,'so that two sets are formed, and these two sets are similar in form, but opposites. The scales to the left are represented individually by the characters A, B, C, and D, and those at the right by the characters a, b, c, and d. 1f

the pin 13 is attached in the uppermost of the openings 12, as indicated in Fig. 1, and the dial is then rotated, the free extremity ofthe pointer 14 will move along either the scale A or c. If the pin 13 is placed in the second opening, the extremity of the pointer will move along either the scale B or b, &c. The scales A, B, C, and D are devoted to the measurement of hip-rafters, while the opposite scales are devoted to the measurement of These different scales are graduated, so that when the dial is set at a certain angle with relation to a xed oint,

such as the point 17a on the casing, t e ex-4 tremity of the pointer will indicate on'the corresponding scale the length of the rafter reluired. The four dierent scales on each si e' correspond to different widths for the building-that is, the outside scales A c correspond to a building width of twenty feet. 1n other words, the uppermost pin position, as shown in Fig. 1, corresponds to a building width of twenty feet, the next position corresponds to a building width ofeighteen feet,

the next to a building width 'of sixteen feet, and the lowest position of the pin corresponds to a building width of fourteen feet. n In this IOO way we are enabled to measure or determine the lengths of rafters, whether hip-rafters or straight rafters` for any iven pitch of roof and for any of the widths o building referred to. Thus in Fig. 3 the pointer is indicating the proper length of a hip-rafter for a building of twenty-feet width with a pitch oi Jforty-five degrees. In Fig. I the instrument is indicating the length of a straight rafter for a building of the same width, but having a pitch of thlrty degrees.

For the purpose of enabling the dial to swing'i'reely we prefer to mount the hub 8 thereot1 on ball-bearings 18, the parts being retained in position by means oi a central pin 19, receiving a nut 20, disposed in the recess 6 at the back andscrewing up against the rear face of the hub 4.

The graduations on the dial enable the device to be used to measure the degree of inclination of a timber already in position. In using the device for'this purpose the body or bar 1 will be laid upon the upper or lower edge of the timber, as will be readily understood. In this way the device may be used as an ordinary level to show whether a beam or iioor is horizontal.

Having thus described our invention, we claim as new and desire to secure by Letters Patentl. An instrument of the class described, comprising iny combination, a dial case, a graduatedy dial rotatably mounted therein, a pointer pivoted on said case, a pin adaptedto be iXed in said dial-and engaging said pointer to guide the same upon said dial, said dial having scales cooperating with said pointer.

2. In an instrument of the class described, in combination, a dial-case, a graduated dial rotatably mounted therein, a pointer Divotally attached to said case and having a Ongitudinally-disposed slot tnerein, a pin passinfr through said slot, means for attaching sai pin to said dial in a plurality of positions, said dial'having scales formed on the'face'tneleo'f cooperating with said pointer and corresponding tothe different positions of said pin, said scales representing rafter lengths.

3. In an instrument of the class described, in combination, a dial-case, a eounterweights ed dial rotatably mounted thereon andi having graduations on the edge thereof, a pointer depending from said case across the face of said dial and having a longitudinal slot therein, a pin passing through said slot, and means for attaching said pin to said dial in a plurality of positions, the said dial having a plurality of curved graduated scales thereon giving the lengths of rafters corresponding to diierent pitches thereof, said scales coperating with said pointer.

In testimony whereor we have signed our names to this speoiiication in the presence of two subscribing witnesses.

WILLIAM WESLEY DWIGANS. JOE M. ADAMS.

Witnesses:

J. W. PATTERsoN. F. L. DEMON. 

